Image Caption: STS49-72-062: Pilanesberg Circular Structure and Platinum Mines,Transvaal, Republic of South Africa The great circular feature isthe root of an old volcano in central South Africa. The entirestructure, 30 miles across, is now a game reserve which includesa herd of five elephants imported from hundreds of miles away,the first seen in the area for a hundred years. Platinum minescan be seen as small, white, angular patches. This area lies 100miles WNW of the gold mining center of Johannesburg.